The present invention relates to a jaw crusher, and particularly to a movable jaw holding mechanism, and an adjusting mechanism for a tip clearance between a movable jaw and a stationary jaw.
Various proposals have been conventionally made for the structure of a jaw crusher, and as examples thereof, those disclosed in Japanese Patent Application Publication No. 5-45300 and Japanese Patent Application Laid-open No. 10-249224, are cited.
FIG. 8 is an explanatory view in a side section of a crusher disclosed in Japanese Patent Application Publication No. 5-45300. Inside a crusher main body 60, a swing jaw 61, having a movable jaw 5, is suspended from an eccentric shaft 62, and a stationary jaw 3 is attached to oppose it. A lower end portion of a toggle block 63 is rotatably attached to the crusher main body 60 with a pin 64. A base end portion of a hydraulic actuator 70 having a frictional force utilizing close fit of a sleeve and a cylinder rod is swingably attached to the crusher main body 60, and its tip end portion is rotatably attached at an upper end portion of the toggle block 63 with a pin 65.
An adjusting hydraulic cylinder 71 is provided in series at a rear end portion of the hydraulic actuator 70. Toggle sheets 66 and 66 each having a groove portion are provided at a lower end portion of the swing jaw 61 and at a center portion of the toggle block 63, and a toggle plate 67 is inserted between the groove portions of both the sheets 66 and 66 with both end portions being slidable. A spring 68 is biased so that the swing jaw 61 and the toggle block 63 always hold the toggle plate 67 between them.
Hydraulic pressure of the adjusting hydraulic cylinder 71 is adjusted at a predetermined set pressure during a crushing operation so that the cylinder rod of the hydraulic actuator 70 is held at an arbitrary position by a frictional force of the sleeve and the cylinder rod, and a clearance between tip end portions of the movable jaw 5 and the stationary jaw 3 is maintained.
FIG. 9 is an explanatory view of a sectional side view of a jaw crusher disclosed in Japanese Patent Application Laid-open No. 10-249224. A swing jaw 61 having the movable jaw 5 is swingably suspended at an eccentric shaft 62 attached at upper portions of left and right side frames 80 and 80, and the stationary jaw 3 is fixedly provided at the side frame 80 to oppose it to form a crushing chamber 6. A toggle block 63 is attached to the side frame 80 by a block support shaft 81 with its base end portion being rotatable. A window 82 having a semicircular portion is provided near a tip end portion of the toggle block 63 at the side frame 80, a semicircular disc-shaped load supporting plate 83 is fitted in the window 82, and a set adjusting plate 84 for adjusting an outlet clearance of the crushing chamber 6 is provided between the load supporting plate 83 and the toggle block 63.
Toggle sheets 66 and 66 each having a groove portion are attached to a lower end portion of the swing jaw 61 and the toggle block 63. A toggle plate 67 is provided between groove portions of both the sheets 66 and 66 so that both ends thereof are slidable, and the lower end portion of the swing jaw 61 is always biased to the toggle block 63 by a spring 85. The toggle block 63 and the side frame 80 are connected by a bare rock type of hydraulic cylinder 86, the toggle block 63 is rotated by a hydraulic cylinder 86 at the time of adjusting the outlet clearance of the crushing chamber 6, and a clearance is provided between the toggle block 63 and the load supporting plate 83 so that the thickness of the set adjusting plate 84 is adjusted.
However, the above-described structures have the following disadvantages.
In the structure disclosed in Japanese Patent Application Publication No. 5-45300, the toggle sheets 66 and 66 are attached to the lower end portion of the swing jaw 61 and the toggle block 63, and the toggle plate 67 is held between both the sheets 66 and 66 to receive a load during crushing. Accordingly, the toggle plate 67 is sandwiched, and the spring 68 is used to hold it, which makes the structures complicated and requires adjustment of the spring 68 each time the tip clearance is adjusted, thus increasing adjustment time. In addition, when they are mounted on vehicles, operating spaces become narrow, which makes adjusting operations themselves difficult.
Since the adjusting hydraulic cylinder 71 is provided at the rear end portion of the hydraulic actuator 70, the total length of the hydraulic cylinder part is long, and since it is horizontally arranged, a total length N of the jaw crusher 61 shown in FIG. 8 is long, which makes a space area large to cause the disadvantage when mounted on a vehicle and the like. Since pressure is always applied to the adjusting hydraulic cylinder 71, energy is wasted. Further, oil leakage occurs, which makes it unstable. A complicated hydraulic circuit structure is necessary to prevent the oil leakage, which makes it expensive.
In the structure disclosed in Japanese Patent Application Laid-open No. 10-249224, as in the structure described above, the toggle plate 67 is sandwiched, and the spring 85 is used to hold it, which makes the structures complicated and requires adjustment of the spring 85 each time the tip clearance is adjusted, thus increasing adjustment time. In addition, when they are mounted on vehicles, operating spaces become narrow, which makes adjusting operations themselves difficult. Further, it adopts the method of preventing breakage of the other components by the toggle plate 67 being bent under excessive load, and a replacement operation of the bent toggle plate 67 is difficult, thus requiring a great deal of time. Furthermore, since adjustment of the outlet clearance of the crushing chamber 6 is made with the set adjustment plate 84, a great deal of time is required for adjustments and thus operation efficiency is low.
The present invention is made in view of the above-described disadvantages, and has its object to provide a compact and light-weight jaw crusher in which life span of parts enduring abrasion is long, a structure is simple, less part is damaged under excessive load with excellent operation efficiency, greater economy is obtained with no energy loss, and an outlet clearance of a crushing chamber is easily adjusted.
In order to attain the above-described object, a first aspect of the jaw crusher according to the present invention is a jaw crusher has the structure including
a stationary jaw fixedly provided at a frame,
a movable jaw which is provided to oppose the stationary jaw and attached swingably with an eccentric drive shaft,
a movable jaw load receiving section attached to the frame, and
a coupling joint which is a connecting member for connecting a lower portion of the movable jaw and the movable jaw load receiving section and swingably connects the lower portion and the movable jaw load receiving section.
According to the above structure, instead of the toggle plate conventionally used, which has a sandwiching structure, the swingable coupling joint, which never comes off and falls, is used for the connecting member for the lower end portion of the movable jaw which receives load during compression crushing of the jaw crusher and the movable jaw load receiving section attached to the frame. Consequently, since the attached spring is not needed, the structure is simplified, and the tip clearance adjusting time can be shortened. Further, the lubrication at the connecting portion is secured, and the frequency of maintenance is reduced with less abrasion, thus improving operation efficiency.
Further, in the jaw crusher, the movable jaw load receiving section may have a structure forming a rotatable link mechanism including a hydraulic cylinder with a close fit mechanism.
According to the above structure, relative movement in the axial direction is locked by friction of the hydraulic cylinder with the close fit mechanism, and therefore the friction part slides when an abnormally large force is applied, thus preventing damage of the connecting portion (coupling joint) of the lower portion of the movable jaw and the movable jaw load receiving section, the rotary link mechanism, the frame and the like. The prior art crushers have the structure in which damaging of the connecting portion (toggle plate) prevents the damage to the other members. Since the length of the hydraulic cylinder with the close fix mechanism can be changed with hydraulic pressure, the adjustment of the clearance between the stationary jaw and the movable jaw is facilitated, and thus operability is improved. Further, since the friction of the hydraulic cylinder with the close fit mechanism locks the movement in the rod shaft direction, the load from the movable jaw is surely set, thus making the optimal strength design possible.
Further, in the jaw crusher, the structure including a hydraulic circuit which makes the hydraulic cylinder with the close fit mechanism open at a time of crushing operation may be made.
According to the above structure, since the hydraulic cylinder with the close fit mechanism is made open at a time of crushing operation, greater economy is obtained with no energy loss, and an accumulator for holding oil pressure for the hydraulic circuit, a leakage prevention valve and the like are made unnecessary, thus simplifying the circuit.
A second aspect of the jaw crusher according to the present invention has the structure including
a stationary jaw fixedly provided at a frame,
a movable jaw which is provided to oppose the stationary jaw and attached swingably with an eccentric drive shaft,
a movable jaw load receiving section attached to the frame, and
a connecting member for connecting a lower portion of the movable jaw and the movable jaw load receiving section,
wherein the movable jaw load receiving section forms a rotatable link mechanism including a hydraulic cylinder with a close fit mechanism,
and the jaw crusher has the structure further including a hydraulic circuit which makes the hydraulic cylinder with the close fit mechanism open at a time of a crushing operation.
According to the above structure, relative movement in the axial direction is locked by friction of the hydraulic cylinder with the close fit mechanism, and therefore when an abnormally large force is applied, the close fit part slides and prevents the damage of the connecting portion, the rotary link mechanism, the frame and the like. Since the length of the hydraulic cylinder with the close fit mechanism can be changed by hydraulic pressure, adjustment of the clearance between the stationary jaw and the movable jaw can be facilitated, thus improving operability. Further, since the relative movement in the axial direction is locked by the friction of the hydraulic cylinder with the close fit mechanism, setting of the load from the movable jaw is surely made, and therefore optimal strength design can be made. Further, at the time of a crushing operation, the hydraulic cylinder with the close fit mechanism is made open, greater economy is obtained with no energy loss, and an accumulator for holding oil pressure in the hydraulic circuit, the leakage prevention valve and the like become unnecessary, thus simplifying the circuit.
Further, in the jaw crusher, the hydraulic cylinder with the close fit mechanism may have the structure having the close fit mechanism of the piston and the cylinder.
According to the above structure, the hydraulic cylinder with the close fit mechanism has the close fit mechanism of the piston and the cylinder, the relative movement in the axial direction is locked with the frictional force by the close fitting and the length in the axial direction is made changeable by hydraulic pressure applied to both end portions of the piston. As a result, a large locking force can be obtained with a small size and the total length can be reduced, thus making it possible to reduce the apparatus in size.
A third aspect of the jaw crusher according to the present invention has the structure including
a stationary jaw fixedly provided at a frame,
a movable jaw which is provided to oppose the stationary jaw and attached swingably with an eccentric drive shaft,
a movable jaw load receiving section attached to the frame, and
a connecting member for connecting a lower portion of the movable jaw and the movable jaw load receiving section,
wherein the movable jaw load receiving section forms a rotatable link mechanism including a hydraulic cylinder with a close fit mechanism, and
wherein the hydraulic cylinder with the close fit mechanism has a close fit mechanism of a piston and a cylinder.
According to the above structure, the relative movement in the axial direction is locked by friction of the hydraulic cylinder with the close fit mechanism, and therefore when an abnormally large force is applied, the close fit part slides and prevents damage of the connecting portion, the rotary link mechanism, the frame and the like. Further, since the length of the hydraulic cylinder with the close fit mechanism can be changed with hydraulic pressure, the adjustment of the clearance between the stationary jaw and the movable jaw can be facilitated, thus improving operability. Furthermore, since the movement in the axial direction is locked by the friction of the hydraulic cylinder with the close fit mechanism, setting of the load from the movable jaw is surely made, and therefore optimal strength design can be made. Further, the hydraulic cylinder with the close fit mechanism has the close fit mechanism of the piston and the cylinder, locks the relative movement in the axial direction with the friction force by the close fitting, and makes the length in the axial direction changeable by the hydraulic pressure applied to both end portions of the piston, thus making it possible to obtain a large locking force with a small size, reduce the total length, and make the apparatus compact.
Further, in the jaw crusher, the structure in which one end portion of the hydraulic cylinder with the close fit mechanism is attached to the frame near the eccentric drive shaft may be made.
According to the above structure, one end portion of the hydraulic cylinder with the close fit mechanism is attached to the frame near the eccentric drive shaft having rigidity, and therefore special reinforcement of the frame for attachment of the hydraulic cylinder becomes unnecessary, thus making it possible to reduce in weight. Further, placement in the substantially vertical direction is made possible, whereby the total length of the jaw crusher can be reduced, the frame can be reduced in weight, and the jaw crusher can be easily mounted on a vehicle.